I was working with Data Kruncher through PM and it's come to my understanding that what you want to do is run all reports against the project file. To that end I came up with a better solutions to the problem:

@echo off

SETLOCAL ENABLEDELAYEDEXPANSION

(set reports=)

for %%i in ("C:\FullPath\x230*.txt") do (set reports=!reports! /rpt:%%i)